A. Field of the invention
The invention relates to micro-miniature identification systems and comprises a method and apparatus for quickly and inexpensively inscribing identifying information on an extremely small workpiece while providing a separate corresponding record of the inscribed information.
B. Prior Art
A micro-miniature personal identification system is described in U.S. Pat. No. 4,027,391, issued June 7, 1977 to Philip Samis. The identification element shown there comprises a small metallic chip on the order of 1.5 millimeters square and one half millimeter in thickness. The chip is designed for insertion in the filling of a tooth and carries personal identifying information such as the recipient's name, and other identifying information permanently inscribed thereon. The characters of the inscription are correspondingly small, of the order of 0.001 to 0.010 inches high.
The size of the chip imposes severe contraints on the handling and inscription of the chip, and conventional engraving techniques, whether chemical, mechanical, or other (e.g. laser) are ill-suited to this operation. To begin with, the very size of the chip imposes stringent requirements on registration of the chip with the implement or agent which is to effectuate the inscription. Further, many of these techniques are economically feasible only when used in a batch-processing operation where large numbers of these chips can be processed at once as is commonly done, for example, in the production of electronic integrated circuits. This effectively precludes the use of such systems in circumstances where only intermittent use may be called for, e.g. in individual dentists' offices. Further, even where the requisite volume for batch processing is present, or the delays imposed by batch processing are acceptable, the difficulties in accurately segregating and further handling the individual chips is substantial, and considerable precautions are required to avoid error.